All Questions
Tagged with cryptocurrency proof-of-work
11 questions
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The specific nature of a 51% attack - in relation to a multiple choice question that I was marked as incorrect on
In a course I'm taking the following question came up:
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54
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What is the difference between Solution-Verification and Challenge-Response variants of Proof of Work;
Sorry if question is really dumb, I am new to crypto :(
If the client provides the solution for the PoW Challenge-Response, in my understanding, the solution of that challenge should be verified. So I ...
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1
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490
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P256 seed problem
I'm reading up on elliptic curves and their history and it seems that people don't trust P256 seed which is defined in FIPS 186-3 on page 89 to be
SEED = c49d3608 86e70493 6a6678e1 139d26b7 819f7e90
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- 11
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Is this simple Proof of Work algorithm based on SHA256 susceptible to length extension attack?
Each block's contents are hashed into 32 bytes using $\operatorname{SHA-256}$ (call this string $a$). In order for the block to be accepted, there must be a 256bit nonce (call this string $b$) ...
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2
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What are alternatives to Proof of Work for consensus of a blockchain that doesn't contain anything of value?
For example, a distributed blockchain that would keep track of the weather. Anyone could add a weather reading, and several of these would be stored in each block, just like transactions in a ...
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Can you elaborate on pBFT for dBFT in relation to PoW and PoS consensus algorithms in layman's terms?
I've read all other related answers and googled this extensively. My intention and background in asking this question is that I am delving into cryptocurrency and blockchain technology in general. ...
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Is the proof-of-work algorithm "Quark" insecure?
I recently found out about Quark here.
Apparently it is a proof-of-work algorithm used by several cryptocurrencies and is based on a single-level hash function, which consists of 9 different levels of ...
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POW with Linear time to solve it?
Any suggestions for A Proof-of-Work algorithm in literature so that the time required for solving it is linear with the puzzle difficulty ??
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Can Bitcoin mining solve Graph Isomorphism-related problems?
Given a cryptographic hash $H:\{0,1\}^*\mapsto\{0,1\}^N$ and data $D\in\{0,1\}^*$, the Hashcash/Bitcoin Proof-of-Work entails finding a nonce $x$ such that $H(x\Vert D)$ begins with $d$ leading zeros, ...
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2
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Can "Approximate Hashing" work in a Proof-of-Work context?
Here is a draft of an article claimed to soon appear in a peer-reviewed conference: Matthew Vilim, Uenry Duwe, Rakesh Kumar, Approximate Bitcoin Mining.
It is proposed to simplifying a SHA-256 engine ...
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How can uniformity of hash functions (e.g. SHA-256) be proved?
In reading about the Bitcoin protocol I noticed how much its proofs-of-work apparently depend on uniformity of the SHA-256 hash function. And so presumably do many other applications.
How do ...
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